I Built 13 Free Tools for Living in Japan — All Open Source

Over the past few months, I've been building free web tools for foreigners living in or traveling to Japan. All static sites, all open source, all hosted on GitHub Pages — zero server costs. Here's what I built and why. The Problem If you've ever moved to Japan or planned a trip there, you know the pain: information is scattered across blog posts, Reddit threads, and outdated government PDFs. I wanted to fix that by building focused, searchable tools. The Tools Daily Life Japan Tax Calculator — Input your salary, get your take-home pay with all deductions calculated (income tax, resident tax, social insurance) Japan Utility Setup Guide — Step-by-step guide for setting up electricity, gas, water, and internet Japan Size Converter — Convert clothing and shoe sizes between Japan, US, UK, EU, and AU systems Money Money Transfer Japan — Compare international transfer services (fees, rates, speed) + scam checker NISA Investment Guide — Compare investment vehicles available in Japan (iDeCo, N